Nonionic surfactants produced by addition polymerization of aliphatic alcohols with alkylene oxides having 2 to 4 carbon atoms in the presence of a catalyst are widely used in various applications such as various detergents, emulsifiers, emulsifiers for emulsion polymerization, dispersants, solubilizers, wetting penetrants, and defoamants.
These nonionic surfactants have been known to enhance performances, such as detergency and emulsifying power by being combined, with other surfactants (J. Am. Oil. Chem. Soc. 62, 1139 (1985)). There are many techniques for the surfactant compositions containing these nonionic surfactants disclosed.
Nonionic surfactants produced by adding ethylene oxide to aliphatic alcohols have problems of reduction in fluidity and separation due to its high melting point and the tendency of easily forming a liquid crystal structure when mixed with water or other surfactant. For overcoming the problems from the viewpoint of ease of handling, there is a proposed method of combining ethylene oxide with propylene oxide or butylene oxide (JP-A 50-116384). Further, WO-A 2008/088647 discloses an alkoxylated nonionic surfactant derived from seed oil. DE-A 3607193, corresponding to U.S. Pat. No. B 4,832,868, discloses a surfactant mixture containing an ether alcohol added with ethylene oxide and/or propylene oxide. DE-A 3643895, corresponding to U.S. Pat. No. B 4,965,014, discloses a surfactant mixture containing an alcohol derivative added with ethylene oxide and/or propylene oxide.